Heating system of vehicle

ABSTRACT

An indoor heating line is arranged to pass through a heater core for a coolant heater and indoor air conditioning, and is provided with a first pump so that coolant can flow. A battery heating line is branched from a downstream point of the heater core and connected to an upstream point of the coolant heater after passing through a battery heat exchange part for temperature-raising a high voltage battery, where the battery heating line includes a first heat exchange flow passage that connects a downstream point of the heater core to a first side of the battery heat exchange part, and a second heat exchange flow passage that connects a second side thereof and an upstream point of the coolant heater, where the first heat exchange flow passage and the second heat exchange flow passage are configured to mutually exchange heat.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims under 35 U.S.C. § 119(a) the benefit ofKorean Patent Application No. 10-2018-0040856 filed on Apr. 9, 2018, theentire contents of which are incorporated by reference herein.

BACKGROUND (a) Technical Field

The present disclosure relates to a heating system of a vehicle, moreparticularly, to the heating system capable of efficiently managingenergy required for indoor air conditioning and heating/cooling of abattery to prevent damage to the battery and reduce the load on aheater.

(b) Description of the Related Art

In recent years, electric vehicles have been developed to solve problemssuch as the implementation of environmentally friendly technologies andenergy depletion. An electric vehicle utilizes a motor that receiveselectrical power from a battery and outputs power. Therefore, theelectric vehicle has been very popular as an environmentally-friendlyvehicle because it does not emit carbon dioxide, produces minimal noise,and has a highly energy efficient motor thereof as compared to aconventional engine.

A battery module is important technology to the electric vehicle, andrecently, research to provide a lightweight battery that is downsizedand has other beneficial characteristics such as a short charge time,etc. has been actively carried out. The battery module should be used inoptimal temperature conditions in order to maintain optimum performanceand long life. However, it is difficult to use the battery module inoptimal temperature conditions due to heat generated during driving andexternal temperature change.

Further, since the electric vehicle does not have a waste heat sourcegenerated or combusted in a separate engine like an internal combustionengine, the electric vehicle performs indoor heating thereof in winterby an electric heater. In addition, since the electric vehicle requireswarm-up in order to improve battery charging and discharging performanceduring cold weather, the electric vehicle uses an electric heater of aseparate coolant heating type. That is, in order to maintain an optimumtemperature environment of the battery module, the electric vehicle hasadopted the technology of separately operating a cooling and heatingsystem for controlling the battery module temperature other than acooling and heating system for indoor air conditioning of the electricvehicle. In other words, the electric vehicle has incorporated twoindependent cooling and heating systems and used one for indoor coolingand heating and the other for battery module temperature control.

However, when operating in the manner described above, energy cannot beefficiently managed, so that it is not possible to travel long distancesbecause of possible short driving distance. The driving range of theelectric vehicle may be reduced over 30% in summer cooling and over 40%in winter heating, so that the winter heating problem, which is not aproblem in the internal combustion engine, becomes even more serious.When a high-capacity Positive Temperature Coefficient (PTC) heater isinstalled to solve the problem of heating in winter, the travel distanceis shortened, and the cost and weight due to the use of a heat pumpbecomes excessive.

Accordingly, the cooling and heating system for indoor air conditioningand the battery cooling and heating system are provided to share acoolant with each other, and thus technologies for improving the heatingand battery temperature-raising efficiency have been attractingattention. However, since the main operating temperature (80° C. ormore) of the heater and the temperature-raising temperature (50° C.) ofthe battery are different from each other, there is a problem that ahigh temperature coolant flows into the battery, causing damage to thebattery, if the sophisticated cooperative control of the heating logicand battery temperature-raising logic is not performed.

The foregoing is intended merely to aid in the understanding of thebackground of the present disclosure, and is not intended to mean thatthe present disclosure falls within the purview of the related art thatis already known to those skilled in the art.

SUMMARY

Accordingly, the present disclosure proposes a heating system of avehicle which efficiently manages the energy required for indoor airconditioning and battery cooling and heating, thereby preventing damageto the battery, and reducing the load of a heater.

The heating system of the vehicle according to the present disclosure inorder to achieve the above object may include an indoor heating linearranged to pass through a coolant heater and a heater core for indoorair conditioning and provided with a first pump so that coolant flowstherein; and a battery heating line branched from a downstream point ofthe heater core and connected to an upstream point of the coolant heaterafter passing through a battery heat exchange part fortemperature-raising a high voltage battery; wherein the battery heatingline further includes: a first heat exchange flow passage that connectsa downstream point of the heater core to a first side of the batteryheat exchange part; and a second heat exchange flow passage thatconnects a second side of the battery heat exchange part and an upstreampoint of the coolant heater; wherein the first heat exchange flowpassage and the second heat exchange flow passage is configured tomutually exchange heat.

The indoor heating line may include a first bypass flow passageconnecting the point where the first heat exchange flow passage isconnected and the point where the second heat exchange flow passage isconnected with each other without going through the battery heatexchange part; and a first valve provided at the first bypass flowpassage or the battery heating line for controlling the coolant flow.

The first valve may be installed at a branch point where the first heatexchange flow passage and one end portion of the first bypass flowpassage branch off or the second heat exchange flow passage and anotherend portion of the first bypass flow passage branch off.

The first valve may be installed at the first heat exchange flow passageor the second heat exchange flow passage.

A battery cooling line may be provided to connect the first side and thesecond side of the battery heat exchange part and equipped with a secondpump so that the coolant can be circulated; and wherein the first valvemay be installed at a branch point where the first heat exchange flowpassage and the battery cooling line branch off or the second heatexchange flow passage and the battery cooling line branch off.

A controller for controlling the opening of the first valve may befurther included; and in the case of indoor and battery heating mode,the controller controls the first valve so that the coolant cancirculate through the indoor heating line, the first heat exchange flowpassage, the battery heat exchange part and the second heat exchangeflow passage.

A controller for controlling the opening of the first valve may befurther included; and in the case of indoor heating mode, the controllercontrols the first valve so that the coolant can circulate through theindoor heating line and the first bypass flow passage.

Some sections in the first heat exchange flow passage and the secondheat exchange flow passage may be thermally connected to each other toform a heat exchange section for heat exchange; and a second bypass flowpassage which connects the heat exchange section of the first heatexchange flow passage and the heat exchange section of the second heatexchange flow passage to each other without passing through the batteryheat exchange part, and a second valve installed on the second bypassflow passage to adjust the coolant flow, may be further included.

A controller for controlling the opening of the second valve may befurther included; and in the case of indoor and battery heating mode,the controller controls the second valve so that the coolant cancirculate through the indoor heating line, the first heat exchange flowpassage, the battery heat exchange part and the second heat exchangeflow passage.

A controller for controlling the opening of the second valve may befurther included; and in the case of indoor heating mode, the controllercontrols the second valve so that the coolant can circulate through theindoor heating line, the first heat exchange flow passage, the secondbypass flow passage and the second heat exchange flow passage.

Some sections in the first heat exchange flow passage and the secondheat exchange flow passage may be thermally connected to each other toform a heat exchange section for heat exchange; and a third bypass flowpassage in parallel connected with the first heat exchange flow passageor the second heat exchange flow passage may be provided on the firstheat exchange flow passage or the second heat exchange flow passage inorder to bypass the heat exchange section.

A third valve for adjusting the coolant flow may be provided at thethird bypass flow passage or the heat exchange flow passage in which thethird bypass flow passage is installed.

The third valve may be operated so that the coolant can flow through theheat exchange flow passage when the coolant temperature is equal to orlower than the set temperature and the coolant can flow through thethird bypass flow passage when the coolant temperature is higher thanthe set temperature.

The first valve may be a 4-way valve that is installed a branch pointwhere the first heat exchange flow passage and end portions of the thirdbypass flow passage and the first bypass flow passage branch off inorder to adjust the coolant flow.

A controller for controlling the opening of the first valve may befurther included; and in the case of indoor and battery heating mode andwhen the coolant temperature is higher than a set temperature, thecontroller controls the first valve so that the coolant can circulatethrough the indoor heating line, the first heat exchange flow passage,the battery heat exchange part and the second heat exchange flowpassage.

A controller for controlling the opening of the first valve may befurther included; and in the case of indoor and battery heating mode andwhen the coolant temperature is equal to or lower than a settemperature, the controller controls the first valve so that the coolantcan circulate through the indoor heating line, the third bypass flowpassage, the battery heat exchange part and the second heat exchangeflow passage.

A controller for controlling the opening of the first valve may befurther included; and in the case of indoor heating mode, the controllercontrols the first valve so that the coolant can circulate through theindoor heating line and the first bypass flow passage.

According to the heating system of the vehicle configured to the abovedescribed structure, the coolant of the indoor heating linetemperature-raised by the heater is arranged in order to pass throughthe battery, thereby quickly temperature-raising the battery.

Particularly, by exchanging heat between the coolant flowing into thebattery and the coolant being discharged from the battery through theheat exchanger so that it is able to prevent the excessive temperaturecoolant from flowing into the battery to prevent damage to the batteryand the medium temperature coolant can be supplied to the heater toreduce the operating load of the coolant heater.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and other advantages of thepresent disclosure will be more clearly understood from the followingdetailed description when taken in conjunction with the accompanyingdrawings, in which:

FIGS. 1 to 2 are drawings showing the operation of a heating system of avehicle according to a first exemplary embodiment of the presentdisclosure;

FIGS. 3 to 7 are drawings variously showing application positions of thefirst valve of the heating system of the vehicle according to the firstexemplary embodiment of the present disclosure;

FIG. 8 is a drawing showing a heating system of a vehicle according to asecond exemplary embodiment of the present disclosure;

FIGS. 9 to 10 are drawings showing a heating system of a vehicleaccording to a third exemplary embodiment of the present disclosure;

FIG. 11 is a drawing showing a heating system of a vehicle according toa fourth exemplary embodiment of the present disclosure; and

FIG. 12 is a graph showing changes in coolant temperature according to aheating system of a vehicle of the present disclosure.

DETAILED DESCRIPTION OF THE DISCLOSURE

It is understood that the term “vehicle” or “vehicular” or other similarterm as used herein is inclusive of motor vehicles in general such aspassenger automobiles including sports utility vehicles (SUV), buses,trucks, various commercial vehicles, watercraft including a variety ofboats and ships, aircraft, and the like, and includes hybrid vehicles,electric vehicles, plug-in hybrid electric vehicles, hydrogen-poweredvehicles and other alternative fuel vehicles (e.g. fuels derived fromresources other than petroleum). As referred to herein, a hybrid vehicleis a vehicle that has two or more sources of power, for example bothgasoline-powered and electric-powered vehicles.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the disclosure.As used herein, the singular forms “a,” “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof. As used herein, the term “and/or”includes any and all combinations of one or more of the associatedlisted items. Throughout the specification, unless explicitly describedto the contrary, the word “comprise” and variations such as “comprises”or “comprising” will be understood to imply the inclusion of statedelements but not the exclusion of any other elements. In addition, theterms “unit”, “-er”, “-or”, and “module” described in the specificationmean units for processing at least one function and operation, and canbe implemented by hardware components or software components andcombinations thereof.

Further, the control logic of the present disclosure may be embodied asnon-transitory computer readable media on a computer readable mediumcontaining executable program instructions executed by a processor,controller or the like. Examples of computer readable media include, butare not limited to, ROM, RAM, compact disc (CD)-ROMs, magnetic tapes,floppy disks, flash drives, smart cards and optical data storagedevices. The computer readable medium can also be distributed in networkcoupled computer systems so that the computer readable media is storedand executed in a distributed fashion, e.g., by a telematics server or aController Area Network (CAN).

Hereinafter, preferred embodiments of the present disclosure will bedescribed in detail with reference to the accompanying drawings. Likereference numerals denote like members throughout the drawings.

FIGS. 1 to 2 are drawings showing the operation of a heating system of avehicle according to a first exemplary embodiment of the presentdisclosure; and FIGS. 3 to 7 are drawings variously showing applicationpositions of a first valve of a heating system of a vehicle according tothe first exemplary embodiment of the present disclosure. Referring toFIGS. 1 to 2, the heating system of the vehicle according the firstexemplary embodiment of the present disclosure may include an indoorheating line 10 arranged to pass through a coolant heater 12 and aheater core 14 for indoor air conditioning and provided with a firstpump 16 so that coolant flows therein; and a battery heating line 20branched from a downstream point of the heater core 14 and connected toan upstream point of the coolant heater 12 after passing through abattery heat exchange part 22 for increasing the temperature of a highvoltage battery. The battery heating line 20 may include a first heatexchange flow passage 24 that connects the downstream point of theheater core 14 to a first side of the battery heat exchange part 22 anda second heat exchange flow passage 26 that connects a second side ofthe battery heat exchange part 22 and the upstream point of the coolantheater 12, and the first heat exchange flow passage 24 and the secondheat exchange flow passage 26 may be configured to mutually exchangeheat.

Since an electric vehicle cannot perform indoor heating by using enginewaste heat, a separate temperature-raising device is required.

The indoor heating line 10 of the present disclosure may be configuredto pass through the coolant heater 12 and the heater core 14 for indoorair conditioning, so that the coolant is temperature-raised whilepassing through the coolant heater 12, and the temperature-raisedcoolant is supplied to the heater core 14, thereby supplying the heatedair to the vehicle interior.

Further, an electric vehicle requires a system for temperature-raisingor cooling a high voltage battery because it can only achieve optimalefficiency by maintaining the high voltage battery at an appropriatetemperature.

Particularly, the battery heating line 20 that temperature-raises thehigh voltage battery by receiving and delivering a high temperaturecoolant discharged from the heater core 14 to the battery heat exchangepart 22, may be arranged according to the present disclosure.

That is, because the indoor heating line 10 and the battery heating line20 are connected to each other, the coolant heated by the coolant heater12 flows through the heater core 14 and the battery heat exchange part22 to achieve heating and battery temperature-raising, thereby simplyimplementing a heating and battery temperature-raising system.

However, if the coolant discharged from the heater core 14 isexcessively high, it may be necessary to properly cool the coolant to besupplied to the battery heat exchange part 22 since the high voltagebattery may fail when the coolant flows into the high voltage battery.

In the present disclosure, the first heat exchange flow passage 24 thatconnects the downstream point of the heater core 14 to the first side ofthe battery heat exchange part 22 and the second heat exchange flowpassage 26 that connects the second side of the battery heat exchangepart 22 to the upstream point of the coolant heater 12 are arranged soas to configure the battery heating line 20, and the first heat exchangeflow passage 24 and the second heat exchange flow passage 26 areconfigured to mutually exchange heat.

Therefore, the coolant cooled while passing through the battery heatexchange part 22 cools the coolant passing through the downstream pointof the heater core 14 to prevent the high temperature coolant from beingdelivered to the high voltage battery, thereby preventing batterydamage.

Herein, the first heat exchange flow passage 24 and the second heatexchange flow passage 26 may be arranged to exchange heat with eachother via a separate heat exchanger, and/or are simply adjacentlyinstalled to exchange heat with each other. This can vary depending onthe particular design or vehicle.

In particular, the indoor heating line 10 in the heating system of thevehicle according to the present disclosure may include a first bypassflow passage 30 connecting the point where the first heat exchange flowpassage 24 is connected with the point where the second heat exchangeflow passage 26 is connected without going through the battery heatexchange part 22; and a first valve 32 provided at the first bypass flowpassage 30 or the battery heating line 20 for controlling the coolantflow.

In a situation where the indoor heating line 10 and the battery heatingline 20 share coolant with each other as in the present disclosure, itis necessary to stop the temperature-raising of the high voltage batterywhen the temperature-raising of the high voltage battery becomesexcessive.

At this time, it is unnecessary to supply the coolant through the heatercore 14 to the battery heat exchange part 22, which can cause damage tothe high voltage battery. Therefore, the present disclosure provides thefirst bypass flow passage 30 and the first valve 32 to prevent damage tothe high voltage battery.

That is, the first bypass flow passage 30 is arranged to connect thepoint where the first heat exchange flow passage 24 is connected and thepoint where the second heat exchange flow passage 26 is connected at theindoor heating line 10, and arranged to selectively received the coolantthrough the heater core 14 by the first valve 32 so that the coolant canonly flow through the indoor heating line 10 for heating. A detaileddescription is provided herein.

In a first embodiment of the heating system of the vehicle, the firstvalve 32 may be arranged at various locations.

That is, the first valve 32 may be installed at a branch point where thefirst heat exchange flow passage 24 and one end portion of the firstbypass flow passage 30 branch off or the second heat exchange flowpassage 26 and another end portion of the first bypass flow passage 30branch off.

FIGS. 1 to 2 show, respectively, that the first valve 32 is installed ata branch point where the second heat exchange flow passage 26 and theother end of the first bypass flow passage 30 are branched. On the otherhand, FIG. 3 shows that the first valve 32 is installed at a branchpoint where the first heat exchange flow passage 24 and one end of thefirst bypass flow passage 30 are branched.

Herein, the first valve 32 may be a 3-way valve so that the coolantpumped from the first pump 16 can be selectively supplied to the batteryheat exchange part 22.

Further, referring to FIGS. 4 and 5, the first valve 32 may be installedon the first heat exchange flow passage 24 or the second heat exchangeflow passage 26.

That is, as shown in FIG. 4, the first valve 32 is installed on thefirst heat exchange flow passage 24 or, as shown in FIG. 5, on thesecond heat exchange flow passage 26.

Therefore, the first valve 32 is arranged so that the high temperaturecoolant discharged from the heater core 14 can be selectivelytransmitted to the battery heat exchange part 22. In particular, thefirst valve 32 may be a 2-way open and close valve. Similarly, if thefirst valve 32 is arranged as an open and close valve that is turned onand off, the disclosure can be produced at a lower cost than whenapplying a 3-way valve.

Alternatively, referring to FIGS. 6 and 7, the heating system of thevehicle of the present disclosure may further include a battery coolingline 70 provided to connect a first side and a second side of thebattery heat exchange part 22 and equipped with a second pump 72 tocirculate the coolant. The first valve 32 may be installed at a branchpoint where the first heat exchange flow passage 24 and the batterycooling line 70 branch off or the second heat exchange flow passage 26and the battery cooling line 70 branch off.

The battery heat exchange part 22 may optionally be cooled using acoolant. Thus, the present disclosure may further include the batterycooling line 70 that connects the first side and the second side of thebattery heat exchange part 22.

As shown in FIGS. 6 to 7, the first valve 32 may be arranged the batterycooling line 70.

FIG. 6 shows that the first valve 32 is installed at a branch pointwhere the first heat exchange flow passage 24 and the battery coolingline 70 branch off, and FIG. 7 shows that the first valve 32 isinstalled at a branch point where the second heat exchange flow passage26 and the battery cooling line 70 branch off.

In particular, the first valve 32 is installed at a branch point wherethe heat exchange flow passage branch from the battery cooling line 70,and may be a 3-way valve to allow or block the coolant flow.

In the first exemplary embodiment, the heating system of the vehicle mayfurther include a controller 60 for controlling the opening of the firstvalve 32. In the case of an indoor and battery heating mode, thecontroller 60 controls the first valve 32 so that the coolant cancirculate through the indoor heating line 10, the first heat exchangeflow passage 24, the battery heat exchange part 22 and the second heatexchange flow passage 26.

That is, in the case that indoor heating and battery temperature-raisingare required, as shown by the arrow in FIG. 1, the first valve 32 iscontrolled so that the coolant can circulate through the indoor heatingline 10, the first heat exchange flow passage 24, the battery heatexchange part 22 and the second heat exchange flow passage 26, therebyperforming heating and battery temperature-raising with the coolantheated by the coolant heater 12.

Also, in the indoor heating mode, the controller 60 may control thefirst valve 32 to cause the coolant to circulate through the indoorheating line 10 and the first bypass flow passage 30.

If the electric vehicle requires only the indoor heating, as shown by anarrow in FIG. 2, the first valve 32 is controlled so that the coolantcan circulate through the indoor heating line 10 and the first bypassflow passage 30, thereby preventing the high voltage battery from beingburned out by the high temperature coolant being transmitted to the highvoltage battery.

On the other hand, FIG. 8 is a drawing showing a heating system of avehicle according to a second exemplary embodiment of the presentdisclosure.

Referring to FIG. 8, in the heating system of the vehicle according tothe second exemplary embodiment, some sections in the first heatexchange flow passage 24 and the second heat exchange flow passage 26are thermally connected to each other to form a heat exchange sectionfor heat exchange, and there is provided a second bypass flow passage 40which connects the heat exchange section of the first heat exchange flowpassage 24 and the heat exchange section of the second heat exchangeflow passage 26 to each other without passing through the battery heatexchange part 22 and a second valve 42 installed on the second bypassflow passage 40 to adjust the coolant flow.

That is, the second exemplary embodiment removes the first bypass flowpassage applied to the indoor heating line 10 and provides the secondbypass flow passage 40 between the first and second heat exchange flowpassages 24 and 26 where the heat exchange takes place, thereby securinga bypass flow passage length having a relatively short flow passagelength.

In this case, it is preferable that the second valve 42 is provided as a3-way valve when installed at a point where the second bypass flowpassage 40 is branched from the heat exchange flow passage, and providedas a 2-way open and close valve when installed on the second bypass flowpassage 40 not passing through the heat exchange flow passage.

The heating system of the vehicle according to the second exemplaryembodiment may further include a controller 60 for controlling theopening of the second valve 42. In the case of indoor and batteryheating mode, the controller 60 controls the second valve 42 so that thecoolant can circulate through the indoor heating line 10, the first heatexchange flow passage 24, the battery heat exchange part 22 and thesecond heat exchange flow passage 26.

That is, in the case that indoor heating and battery temperature-raisingare all required, the second valve 42 is controlled in order to blockthe coolant flow toward the second bypass flow passage 40 so that thecoolant flows along the indoor heating line 10, the first heat exchangeflow passage 24, the battery heat exchange part 22 and the second heatexchange flow passage 26, thereby achieving battery temperature-raising.On the other hand, in the indoor heating mode, the controller 60 maycontrol the second valve 42 to cause the coolant to circulate throughthe indoor heating line 10, the first heat exchange flow passage 24, thesecond bypass flow passage 40 and the second heat exchange flow passage26.

That is, if the electric vehicle requires only the indoor heating, thesecond valve 42 is controlled to allow the coolant to flow toward thesecond bypass flow passage 40, thereby preventing the coolant from beingunnecessary transmitted to the battery heat exchange part 22.

FIGS. 9 to 10 are drawings showing a heating system of a vehicleaccording to a third exemplary embodiment of the present disclosure.

Referring FIGS. 9 to 10, in a heating system of a vehicle according tothe third exemplary embodiment, some sections in the first heat exchangeflow passage 24 and the second heat exchange flow passage 26 arethermally connected to each other to form a heat exchange section forheat exchange, a third bypass flow passage 50 in parallel connected withthe first heat exchange flow passage 24 or the second heat exchange flowpassage 26 may be provided on the first heat exchange flow passage 24 orthe second heat exchange flow passage 26 in order to bypass the heatexchange section.

Herein, a third valve 52 for adjusting the coolant flow may be providedat the third bypass flow passage 50 or the heat exchange flow passage inwhich the third bypass flow passage 50 is installed. It is preferablethat the third valve 52 installed at the third bypass flow passage 50 orthe heat exchange flow passage is a 2-way open and close valve.

That is, the third exemplary embodiment adds the third bypass flowpassage 50 and the third valve 52 to the configuration of the firstexemplary embodiment. FIGS. 9 to 10 all show the configuration that thethird valve 52 is installed on the third bypass flow passage 50.However, there is a difference in that the third bypass flow passage 50is installed at the first heat exchange flow passage 24 in FIG. 9 but atthe second heat exchange flow passage 26 in FIG. 10.

The third bypass flow passage 50 may be arranged in order to increasethe battery temperature-raising efficiency by transmitting the heatedcoolant by the coolant heater 12 to the battery heat exchange part 22without exchanging heat between the first and second heat exchange flowpassages 24 and 26.

Therefore, the third valve 52 may be operated so that the coolant canflow through the heat exchange flow passage when the coolant temperatureis equal to or lower than a set temperature and the coolant can flowthrough the third bypass flow passage 50 when the coolant temperature ishigher than the set temperature.

That is, the third valve 52 may be provided as a thermostat and can beopened or closed according to the coolant temperature without anyadditional control to control whether the coolant will flow through thethird bypass flow passage 50.

In the third exemplary embodiment, the first valve 32 may be operatedthe same as the first exemplary embodiment but the third valve 52 may beoperated depending on the coolant temperature. The third valve 52 isclosed when the coolant temperature is below the set temperature so thatthe coolant does not pass through the third bypass flow passage 50, butopened when the coolant temperature is greater than the set temperatureso that the coolant can be transmitted to the battery heat exchange part22 through the third bypass flow passage 50 without exchanging heat anddeteriorating thermal efficiency of the coolant.

Therefore, it is possible to rapidly temperature-raise the high voltagebattery even under coolant temperature deteriorated conditions.

FIG. 11 is a drawing showing a heating system of a vehicle according toa fourth exemplary embodiment of the present disclosure. Referring toFIG. 11, in the heating system of the vehicle according to the fourthexemplary embodiment, the first valve 32 is a 4-way valve that isinstalled a branch point where the first heat exchange flow passage 24and end portions of the third bypass flow passage 50 and the firstbypass flow passage 30 branch off in order to adjust the coolant flow.

That is, the fourth exemplary embodiment is similar to the thirdexemplary embodiment but proposed to reduce the number of application ofthe valve so that the manufacturing cost can be reduced.

A controller 60 for controlling the opening of the first valve 32 may befurther included. In the case of indoor and battery heating mode andwhen the coolant temperature is higher than a set temperature, thecontroller 60 controls the first valve 32 so that the coolant cancirculate through the indoor heating line 10, the first heat exchangeflow passage 24, the battery heat exchange part 22 and the second heatexchange flow passage 26.

That is, when the coolant temperature is higher than the settemperature, the first valve 32 is provided so that the coolantdischarged from the coolant heater 12 is cooled to be transmitted to thebattery heat exchange part 22, thereby preventing the high voltagebattery from being damaged.

Further, In the case of indoor and battery heating mode and when thecoolant temperature is equal to or lower than the set temperature, thecontroller 60 controls the first valve 32 so that the coolant cancirculate through the indoor heating line 10, the third bypass flowpassage 50, the battery heat exchange part 22 and the second heatexchange flow passage 26.

Therefore, when the coolant temperature is equal to or lower than theset temperature, by transferring the coolant to the battery heatexchange part 22 without heat loss, it is possible to secure the batterytemperature-raising efficiency to the maximum.

In case of indoor heating mode, the controller 60 controls the firstvalve 32 so that the coolant can circulate through the indoor heatingline 10 and the first bypass flow passage 30.

FIG. 12 is a graph showing the change in the coolant temperature by aheating system of a vehicle of the present disclosure. As shown in FIG.12, as the first and second heat exchange flow passages areheat-exchanged with each other, the temperature of the coolant suppliedto the battery heat exchange part is reduced to prevent the high voltagebattery from being burned, and the coolant temperature supplied to thecoolant heater is increased to minimize the load of the coolant heater.

In addition, a battery chiller for heat-exchanging with a radiator and arefrigerant line may be provided the battery cooling line 70. Also, awaste heat exchanger for heat-exchanging with an electric componentscooling line may be provided in the flow passage bypassing the radiator.

According to the heating system of the vehicle having theabove-described structure, the coolant of the indoor heating line havingits temperature increased by the heater passes through the battery sothat the battery can be quickly raised in temperature.

Particularly, by exchanging heat between the coolant that flows into thebattery and the coolant that is discharged from the battery through theheat exchanger, it is possible to prevent excessive high temperaturecoolant from flowing into the battery, thereby preventing damage to thebattery and middle temperature coolant is supplied to the coolant heaterso that it is able to reduce operation load of the coolant heater.

Although specific embodiments of the present disclosure has beendescribed and illustrated, those skilled in the art will appreciate thatvarious alternations and modifications are possible without departingfrom the technical spirit of the present disclosure as disclosed in theappended claims.

What is claimed is:
 1. A heating system of a vehicle, comprising: anindoor heating line arranged to pass through a coolant heater and aheater core for indoor air conditioning and provided with a first pumpso that coolant flows therein; and a battery heating line branched froma downstream point of the heater core and connected to an upstream pointof the coolant heater after passing through a battery heat exchange partfor temperature-raising a high voltage battery; wherein the batteryheating line further comprises: a first heat exchange flow passage thatconnects a downstream point of the heater core to a first side of thebattery heat exchange part; and a second heat exchange flow passage thatconnects a second side of the battery heat exchange part and an upstreampoint of the coolant heater; wherein the first heat exchange flowpassage and the second heat exchange flow passage are configured tomutually exchange heat.
 2. The heating system of the vehicle of claim 1,wherein the indoor heating line further comprises: a first bypass flowpassage connecting the point where the first heat exchange flow passageis connected and the point where the second heat exchange flow passageis connected with each other without going through the battery heatexchange part; and a first valve provided at the first bypass flowpassage or the battery heating line for controlling the coolant flow. 3.The heating system of the vehicle of claim 2, wherein the first valve isinstalled at a branch point where the first heat exchange flow passageand one end portion of the first bypass flow passage branch off or thesecond heat exchange flow passage and another end portion of the firstbypass flow passage branch off.
 4. The heating system of the vehicle ofclaim 2, wherein the first valve is installed at the first heat exchangeflow passage or at the second heat exchange flow passage.
 5. The heatingsystem of the vehicle of claim 2, further comprising a battery coolingline provided to connect the first side and the second side of thebattery heat exchange part and equipped with a second pump so that thecoolant can be circulated; and wherein the first valve is installed at abranch point where the first heat exchange flow passage and the batterycooling line branch off or the second heat exchange flow passage and thebattery cooling line branch off.
 6. The heating system of the vehicle ofclaim 2, further comprising: a controller for controlling the opening ofthe first valve; and in the case of indoor and battery heating mode, thecontroller controls the first valve so that the coolant can circulatethrough the indoor heating line, the first heat exchange flow passage,the battery heat exchange part and the second heat exchange flowpassage.
 7. The heating system of the vehicle of claim 2, furthercomprising: a controller for controlling the opening of the first valve;and in the case of indoor heating mode, the controller controls thefirst valve so that the coolant can circulate through the indoor heatingline and the first bypass flow passage.
 8. The heating system of thevehicle of claim 1, wherein: some sections in the first heat exchangeflow passage and the second heat exchange flow passage are thermallyconnected to each other to form a heat exchange section for heatexchange; and a second bypass flow passage which connects the heatexchange section of the first heat exchange flow passage and the heatexchange section of the second heat exchange flow passage to each otherwithout passing through the battery heat exchange part, and a secondvalve installed on the second bypass flow passage to adjust the coolantflow, are further included.
 9. The heating system of the vehicle ofclaim 8, further comprising: a controller for controlling the opening ofthe second valve; and in the case of indoor and battery heating mode,the controller controls the second valve so that the coolant cancirculate through the indoor heating line, the first heat exchange flowpassage, the battery heat exchange part and the second heat exchangeflow passage.
 10. The heating system of the vehicle of claim 8, furthercomprising: a controller for controlling the opening of the secondvalve; and in the case of indoor heating mode, the controller controlsthe second valve so that the coolant can circulate through the indoorheating line, the first heat exchange flow passage, the second bypassflow passage and the second heat exchange flow passage.
 11. The heatingsystem of the vehicle of claim 2, wherein: some sections in the firstheat exchange flow passage and the second heat exchange flow passage arethermally connected to each other to form a heat exchange section forheat exchange; and a third bypass flow passage in parallel connectedwith the first heat exchange flow passage or the second heat exchangeflow passage is provided on the first heat exchange flow passage or thesecond heat exchange flow passage in order to bypass the heat exchangesection.
 12. The heating system of the vehicle of claim 11, wherein athird valve for adjusting the coolant flow is provided at the thirdbypass flow passage or the heat exchange flow passage in which the thirdbypass flow passage is installed.
 13. The heating system of the vehicleof claim 12, wherein the third valve is operated so that the coolant canflow through the heat exchange flow passage when the coolant temperatureis equal to or lower than the set temperature and the coolant can flowthrough the third bypass flow passage when the coolant temperature ishigher than the set temperature.
 14. The heating system of the vehicleof claim 11, wherein the first valve is a 4-way valve that is installeda branch point where the first heat exchange flow passage and endportions of the third bypass flow passage and the first bypass flowpassage branch off in order to adjust the coolant flow.
 15. The heatingsystem of the vehicle of claim 14, further comprising: a controller forcontrolling the opening of the first valve; and in the case of indoorand battery heating mode and when the coolant temperature is higher thana set temperature, the controller controls the first valve so that thecoolant can circulate through the indoor heating line, the first heatexchange flow passage, the battery heat exchange part and the secondheat exchange flow passage.
 16. The heating system of the vehicle ofclaim 14, further comprising: a controller for controlling the openingof the first valve is further included; and in the case of indoor andbattery heating mode and when the coolant temperature is equal to orlower than a set temperature, the controller controls the first valve sothat the coolant can circulate through the indoor heating line, thethird bypass flow passage, the battery heat exchange part and the secondheat exchange flow passage.
 17. The heating system of the vehicle ofclaim 14, further comprising: a controller for controlling the openingof the first valve; and in the case of indoor heating mode, thecontroller controls the first valve so that the coolant can circulatethrough the indoor heating line and the first bypass flow passage.